48 BULLETIN 1005, U. S. DEPARTMENT OF AGRICULTURE. 
loam, and loam were mapped in the two counties. The Portsmouth 
series is represented to a limited extent by the sandy loam and the 
loam. 
Soils of the Elkton series are rather widely distributed in these two 
counties, as well as elsewhere on the Peninsula. The surface soils of 
this series are gray to ash-colored; the subsoils are pale gray, mottled 
with yellow and rusty brown stains. The subsoil is usually under- 
lain by gray, sandy material, frequently saturated with water. The 
subsoil is usually compact and stiff but not especially plastic. Three 
types, the Elkton sandy loam, fine sandy loam, and loam were en- 
countered in the soil survey of Accomac and Northampton Counties. 
Some areas of fresh-water swamp also occur. 
The tidal marsh areas do not form an integral part of the agricul- 
tural upland area. 
The dune sand is too coarse textured to retain sufficient moisture 
for the needs of ordinary agricultural crops, and it does not contribute 
to the tilled area of the section. 
Among these different soils drainage and its consequent modifica- 
tions of soil characteristics constitute the most important distinctions, 
controlling the extent and kind of agricultural occupation to a marked 
degree. 
The Norfolk fine sand and the soils of the Sassafras series are the 
best drained agricultural soils of the region. They are generally 
cleared and occupied for some form of cropping. The soils of the 
Keyport series are fairly well drained and, by the use of open farm 
ditches, are rendered suitable for the production of the majority of 
crops common to the latitude. The soils of the Elkton series always 
require supplementary drainage to suit them to cropping, and even 
then their crop uses are somewhat restricted. They are not so exten- 
sively tilled as soils of the preceding series. The soils of the Ports- 
mouth series are swanipy or semiswampy in their naturaL condition, 
and, as yet, only small areas have been provided with adequate arti- 
ficial drainage and brought under cultivation. Such areas as have 
been improved are usually included within areas of more valuable 
soils. The tidal marsh and swamp are undrained and utilized to 
only a small extent for pasture. Dune sand is of little agricultural 
value. 
DETAILED CROP AND SOIL MAP. 
Onley Area. 
To make a detailed study of the characteristic agricultural soils of 
the Eastern Shore of Virginia counties, particularly with respect to 
their uses for truck crop production, a soil and crop survey of a small 
area around Onley in Accomac County was undertaken in 1916. 
This detailed survey covers 1,777 acres, or approximately 2f square 
